欧亚大陆风云影像线性构造信息提取及其地质分析

通过欧亚大陆风云影像的空间增强、光谱增强、辐射增强等系列处理和地质解释 ,提取了发育于该区的各种线性构造的相关信息。根据性质和规模将线性构造划分为大洋俯冲带、大陆俯冲带、大陆碰撞带、巨型线性构造、区域线性构造和局部线性构造等六类。文中重点介绍了乌拉尔—阿曼巨型线性构造带和阿尔卑斯大陆碰撞带的影像特征和地质意义。根据各类线性构造的特征和相互关系 ,突出了乌拉尔—阿曼和伊尔库茨克—横断山两条巨型线性构造带的地位 ,并以它们为界划分了三个构造域 :西亚构造域以印度板块的俯冲为特色 ,导致青藏高原的隆升和陆内强烈变形 ;东亚构造域最为重要的特征是太平洋板块的俯冲 ,形成一系列岛弧体系 ,并使大陆内部出现大量岩浆活动和强烈的构造变动 ;欧洲构造域主要为非洲—阿拉伯板块与欧洲板块的碰撞 ,二者之间没有明显的俯冲带 ,而有一个较宽广的接触带 ,强烈的变形集中在这一带内 ,而大陆内部的构造变动比较微弱。这种构造格局在欧亚大地水准面异常图上有明显反映 ,表明与深部地质作用过程有关。三个构造域的主导线性构造的方向组成了一个向南弯曲的弧形 ,弧顶位于西亚构造域。大陆巨型线性构造带呈经向和纬向展布 ,具长期发育特征 ,从更大尺度上看 ,板块边界线性构造也是呈经向和纬?

The information extraction and its geologic analysis of the Eurasia lineaments using the Fengyun image

By processing the Fengyun satellite image of Eurasia with procedures of spatial enhancement, spectra enhancement, radiation enhancement, etc., and adopting its geologic interpretation, we have extracted the correlation information of manifold lineaments developed in this area. The lineaments are classified into six categories, i.e., ocean subduction, continental subduction, continental collision, giant lineament, territorial lineament, and local lineament according to their characteristics and dimensions. In this paper, we put emphasis on the introduction of the image characteristics and geological significance of Urals-Oman giant lineament and Alps continental collision. Based on the characteristics and correlation of each kind of lineaments, we give prominence to the status of the two giant lineaments, which were embodied by Urals-Oman and Irkutsk-Hengduan Mountain; and divide the Eurasia into three tectonic domains, namely, the west-Asia tectonic domain, the east-Asia tectonic domain, and the Europe tectonic domain, bordered by these two giant lineaments. The feature of west-Asia tectonic domain is the subduction of the India plate, which caused the uplifting of Qinghai-Tibet Plateau and the strong intracontinental deformation. The prominent feature of east-Asia tectonic domain is the subduction of the Pacific plate, along with which a series of island-arc system were formed, and lots of magmatic activities and strong tectonic transformation were found in the interior continent. The primary feature of Europe tectonic domain is the collision between the Africa-Arabia plate and the Europe plate; there is no obvious subduction but a broad contact-zone with strong deformation; and the intra-continental tectonic transformation is comparatively feeble in Europe tectonic domain. The direction of the dominant lineaments of the three tectonic domains composes an arc bending south, and the arc apex situates at the west-Asia tectonic domain. The continental giant lineament zones are longitudinally or latitudinally distributed and with the characteristic of long-term development. On a larger scale, the lineaments of the plate boundaries are also longitudinal or latitudinal in distribution. Moreover, the continental lineaments and the oceanic lineaments are closely related. Considering all of the above facts, we stress the point that the earth rotation as a dynamic cause of the formation of various geological structures should not be neglected.